package com.itheima.sh.filter;

import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.GlobalFilter;
import org.springframework.core.annotation.Order;
import org.springframework.http.HttpStatus;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.http.server.reactive.ServerHttpResponse;
import org.springframework.stereotype.Component;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Mono;

/**
 * @Description: 全局过滤器 实现登录拦截功能
 * @Version: V1.0
 */
//@Order(1)   // 值越小越优先执行
//@Component
public class LoginFilter implements GlobalFilter {

    /**
     * 拦截过滤方法
     *
     * @param exchange
     * @param chain
     * @return
     */
    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {

        //token=admin  登录， 否则就拦截
        // 1 exchange获取req res
        ServerHttpRequest request = exchange.getRequest();
        ServerHttpResponse response = exchange.getResponse();
        // 2 获取参数 token
        String token = request.getQueryParams().getFirst("token");

        //2.1 没有获取到token 拦截
        if (token == null) {
            response.setStatusCode(HttpStatus.UNAUTHORIZED);  // 401
            return response.setComplete();
        }

        //2.2 判断 token=admin 不等于 拦截
        if (!"admin".equals(token)) {
            response.setStatusCode(HttpStatus.UNAUTHORIZED);  // 401
            return response.setComplete();
        }

        //3 放行
        return chain.filter(exchange);
    }

}
